It Might Be A Simple Answer

[tosh23]

Right here we go....

f650 gs 2004 twin spark 9000 miles, Water pump done and full service, new chain and sprockets (bmw) Rear swing arm removed and everything regreased. Exhaust off for cleaning. Ive had a little problem with the sump plug but thats all fixed now..

Everything is fine untill in top gear, It sounds like a rattle'n top gear tooth comming off the main shaft. It's quite loud because I can hear it on my bike riding behind the wife on her gs.
Throttle on or off makes no difference, but I havent tried freewheeling in top yet, I will do that tomorrow,
The chain was set to 45mm and tonight ive ajusted it to 35mm.
The oil is half way on the dip stick after stoping the engine for 5 mins and screwing the dipstick down all the way.
Wheel alignment is good and the centre stand has been removed....

I will keep trying different things but more brains are better than one......Tosh

 

[Deleted account S A]

Hello Tosh, Is it still noisy doing the same speed when in fouth gear?, If no then try freewheeling as you will stated, If still noisy when freewheeling could be a wheel bearing, Good luck

 

[john_aero]

check the output shaft seal?

bust as andy said prob wheel bearing

 

[tosh23]

Well Guys,
Thanks for the ideas. I striped the rear end today and found the chain out of alignment ALOT...I found out why, the bike wasn't straight when I used the string....IDIOT>>>>>>>
Anyhoo I found the problem..

The old sprocket has vibration dampers on either side..

The new one has nothing on either side..

I removed the new one and installed the old one back on...Then went for a test ride, All quiet and back to normal..So it was the new sprocket that hasn't got any noise dampers and this is what I am hearing...Funny tho' it only rattles in top gear....Anyhoo cheers guys......Tosh

 

[brassmonkey001]

Well Guys,
Thanks for the ideas. I striped the rear end today and found the chain out of alignment ALOT...I found out why, the bike wasn't straight when I used the string....IDIOT>>>>>>>
Anyhoo I found the problem..

The old sprocket has vibration dampers on either side..

The new one has nothing on either side..

I removed the new one and installed the old one back on...Then went for a test ride, All quiet and back to normal..So it was the new sprocket that hasn't got any noise dampers and this is what I am hearing...Funny tho' it only rattles in top gear....Anyhoo cheers guys......Tosh

I think you'll find that's standard. You won't get a sprocket with those dampers on again AFAIK they are only fitted at the factory. It was most likely the misalignment causing the noise.
Plenty of life left in the old sprocket yet though.

 

[tosh23]

When I striped down the bike for cleaning I cut off the chain..DOH..
I then tried to get a soft link to reinstall the old chain but because its an endless chain the soft links wont fit...You cant mix old with new so the whole drive system was replaced....Tosh

 

[brassmonkey001]

When I striped down the bike for cleaning I cut off the chain..DOH..
I then tried to get a soft link to reinstall the old chain but because its an endless chain the soft links wont fit...You cant mix old with new so the whole drive system was replaced....Tosh

Greg Masters does (or used to) supply chains with links.
And with the 650 you'll find that the front sprocket will wear out twice as fast as the rear so many folk (myself included) replace the front when it's worn out and re-use the chain & rear sprocket.

 

[tosh23]

Greg Masters does (or used to) supply chains with links.

I could of bought just a chain for £50 ish but BMW full kits were only a few pounds more.
In reguard to the front sprocket, If it needs a new one before the rear and the chain had done 10,000 or more the I will just put the old one on an already well used chain......If you and others do it then its alright with me........Tosh

 

[tosh23]

Im just wondering if anyone else has noticed an increase in front sprocket noise after a new one has been fitted.........Tosh

 

[Jona]

Just out of interest .... Can these dampers be bought?

Already ordered my new Renthal sprockets so please don't say I'll need OEM

 

[tosh23]

Renthal are ok, The reason I bought OEM is that on some sprockets they are loose on the output shaft due to bad engineering and they should be a very tight fit with no play what so ever..OEM parts are not to badly priced but ive used Rethnal with all my previous bike and found them great